Case-shift mechanism for typewriters



March 22 1927.;

O. A. HOKANSON ET AL CASE SHIFT lMIiIl'IAXISlW FOR TYPEWRITERS Filed Oct. 5, 1925 3 Sheets-Sheet l [maf/WUR; a' MMM dif/f 'jugar t 5%).5.

22 19 March 2? o. A. HOKANSQN ET AL CASE SHIFT MECHANISM FOR TYPEWRITERS Filed oct. s, 125 n 3 Sheets-x-Shea'', 2

` Y LEM Mmh 2 HM o. A. Hommsom ET AL CASE SHIFT MECHANISM FOR TYPEWRITERS Filed Oct. 5, 1925 3 Shee'ks-Sheet 5 jim/mmm Q. www

i5 /W/L Patented Mar. 22, 1927.

UNITED STATES PATENT OFFICE.

OTTO A. HOKANSON AND 'IAMES F. KOCA. OF WOODSTOCK, ILLINOIS, ASSIGNORS TO WOODSTOCK TYPEWRITER COMPANY, OF WOODSTOCK, ILLINOIS, A CORPORATION OF ILLINOIS.

CASE-SHIFT MECHANISM FOR TYPEWRITERS.

Application led October 5, 1925.

This invention'relates to typewriter mechanism having power actuated apparatus for operating the moving parts.

The object of the invention is to provide mechanism of the class named in which the case shift is eiiected by means of a power actuated device and in which actuating mechanism of improved construction and operation is employed.

The invention is exemplified in the combination and arrangement o' parts shown in the accompanying drawings and described in the following specification. and itl is more particularly pointed out in the appended claims.

In the drawings- Fig. 1 is a side elevation ot' a portion ot a typewriter having one embodiment of the present invention applied thereto;

Fig. 2 is a fragmentary view looking from the right in Fig. 1;

Fig. 3 is a vertical sectional view taken just insidel the side frame ot the type- Writer;

25, Fig. 4 is a fragmentary elevation showing a modified-detail; and

Fig. 5 is a view looking from the right in Fig. 4. with parts omitted.

The numeral 10 iu Fig. l ot' the drawings designates a portion of the side frame otl a typewriter which supports an electric solenoid 11 having a plunger 12. Current is supplied to the solenoid 11 from any suitable source through conductors 13 and 14. The conductor 14 is connected to a binding ost 15 carried by an insulating block 16 adjustably secured to an arm 17 by means The arm 17 is pivotally mounted on the frame of the machine and is provided with an extension 19 having an inclined slot 20. The inclined slot 2O is engaged by a pin 21 carried by a link 22 having sliding connection with a screw 23 on the side of the machine frame. The upper end of the link 22 is pivoted at 24 to a hand lever 25. .The hand lever 25 is pivoted at 26 and carries a pin 2T which engages openings 28 in an index plate 29. A spring 30 lnormally holds the pin 27 in engagement with one of theopenings 28.. The lever basa finger-plece 31 by means of which it. may be drawn outwardly against the tension of the spring 30 ot screws 18.

Serial No. 60,395.

to shift the pin 27 from one to another of the holes 28, thus raising or lowering the link22. This movement ot' the link 22 will swing the arm 17 forward and rearwardly, shifting the position of the insulator block 16 and the binding post 15. The binding post 15 carries a Contact point 32 for engaging a corresponding point 33 on a lever 34. The lever 34 swings about a pivot 35 en the frame of the machine and, is connected with a lead 36 which extends through switch mechanism 3T and conductor 38 to the source of power. The lever 34 has a tail-piece 39 which carries a slide 40 normally' drawn downwardly by a spring 41. An arm 42 is secured to a rock shaft 43 which extends across the frame of the machine. 'lhe arm 42 is provided with a lug 44 which engages a projection 45 on the tail-piece 39. rl`he slide 4() is provided -with a projection 46 which is normally positioned just above the lug 44. A spring 47 is connectedto t-he rock shaft 43 and to the lever 34 tending to rotate the rock shaft in a clockwise direction and to swing the contact 33 toward the contact 32. The lug 44 engaging th'e projection 45 holds the contact. 33 out of engagement against the tension of the spring 4T. A. liar 49 is secured to the rock shaft 43 and extends across the frame of the machine in position to be engaged by Contact nieml'liers 5t) on the key levers 51, as shown in When a key lever is depressed the rock shal't 43 is moved in a counter-clockwise direction raising the lug 44 out of engagement with the projection 45 and permitting the spring 4T to swing the contact 33 against the contact 32 thus closing the circuit throuoh the solenoid 11. This will energize t e solenoid and draw the plunger 12 upwardly. The plunger 12 is provided with a'pawl 52 which engages a ratchet wheel 53 on a shaft 54 exending across.- the machine. The shaft 54 is provided with teeth 55 which are moved in a coimter-cloekwise direction each time the ratchet is operated by the solenoid. -r1`he type bars 56 are pivoted at- 57 in the usual way and provided with sublevers 58 which carry actuators 59 having teeth 60 in position to engage the teeth 55. Then a key lever is depressed the actuator 59 'corresponding to that key lever is moved downwardly by a contact finger 61 into the path of the teeth 55 so that when the soienoid is energized the actuator is moved forwardly to operate the corresponding type bar 56. At the forward end of the movement of the actuator 59 it is disengaged from the teeth 55 by an adjustable stop 62 which engages a cam surface 63 on the actuator 59. A roller 64 is carried on an arm 65 pivoted at 66 on the frame of the machine and engages a star-wheel 67 to prevent overthrow of the ratchet wheel 53 when operated by the solenoid. A second arm-68 is pivotally mounted at 66 on the frame of the machine and is provided with an upward extension 69 having a finger 70 adjustably mounted thereon by screws 71 and 7 2. When the solenoid is energized the finger is moved to the left, as viewed in Fig. 1, and engages a pin 73, Fig. 2, carried by the tailpiece 39. This swings the tail-piece 39 to the left and moves the contact 33 out of engagement with the contact 32.

The spring 41 is placed under tension by the lug 44 when the arm 42 is moved upwardly by rotation of the rock shaft 43. As soon as the tail-piece 39 is moved to the left the projection 46 will clear the lug 44 and the spring 41 will move the projection 46 behind the lug 44 thus locking the tail-piece 39 in position to hold the contact 33 out of engagement with the contact 32. When the key lever is released the lug 44 will move from the projection 46 onto the projection 45 thus retaining the contacts 32 and 33 out of engagement. It will thus be seen that upon depression of a key lever the actuator tooth 60 is moved into the path of one of the teeth 55 after which the circuit is closed by the contact points 32 and 33 and the solenoid 11 energized to impart partial rotation to the shaft 54 thus operating the type bar. Immediately upon operation of the solenoid the contact is automatically broken and locked in open position by the mechanism connected with the plunger 12 which returns the lever 34 to its inactive position.

At each side of the machine there is provided a case shift lever 75 having a projection 76 arranged to engage the bar 49 and oscillate the shaft 43 to close the solenoid circuit through the mechanism already described. The case shift lever 75 is provided with a pin 77 which engages a slot 78 on a lever 79 pivotally mounted at 80. The lever 79 carries a downwardly projecting arm S1 having a forwardly bent extension 82. The extension 82 is provided with a pin 83 which underlies a linger-piece 84 secured to a stud shaft 85 journaled in the side of the machine frame. The stud shaft 85 has an arm 86 secured thereto which carries a pin 87'engaging a slot 88 in a plate 89. The plate 89 is slidably mounted on a stud 90 projecting from the frame of the machine and also has sliding connection with a stud 91 on a lever 92, the lever 92 being pivoted on the stud 90. The plate 89 is provided with a nose-piece 93 which normally clears a pin 94 on the plunger 12, but whenthe stud shaft 85 is oscillated by the extension 82 of the lever 81 the nose-piece 93 will be projected into the path of the pin 94. This occurs on depression of a shift key prior to engagement of the contacts 32 and so that when the solenoid is energized the plate 89 will be swung upwardly about the pivot 90 and the lever 92 will be given a partial rotation in a clockwise direction, as viewed in Fig1 1. The lever 92 has a pivotal sliding engagement at 95 with an arm 96 fixed to a shaft 97 which extends across the frame of the machine. The shaft 97 has upwardly projecting arms 98 which are connected by springs 99 with downwardly projecting arms 100 connected with the shift frame 101. The shift frame 101 is pivoted at 102 on the typewriter frame and carries a shift rail 103 on which a roller 104 travels, the roller 104 being arranged to support the platen carriage in the usual manner so that when the shift rail 103 is raised the platen carriage will be shifted. It is thus seen that depression of the shift lever will first position the nose-piece 93 to be actuated by the solenoid after which the shift frame is raised through connecting levers and the spring 99. Immediately after operation of the solenoid it will be de-enerv'ized by the mechanism already described. t is, however, desirable to sustain the platen in its upper position until the shift lever is released. This is accomplished by means of -an arm 105 secured to the shaft 97 in position to engage a roller 106 carried by a lever 107 pivoted at 108 on the lever 81. A spring 109 normally urges the roller 106 rearwardly against a stop 110 on the lever 81. When the shift key is depressed the lever 81 moves rearwardly past the forward end of the arm 105 so that the roller 10G is disposed beneath the cam surface 111 at the end of the arm 105. As soon as the shaft 97 is actuated by the solenoid the arm 105 will be moved downwardly and will pass the roller 106. which is permitted to spring inwardly by the elasticity of the spring 109. The spring'109 immediately moves the roller 106 rearwardly 'above the end of the arm 105 and against the stop lug 112. This will prevent return rotation of the shaft 97 and hold the platen carriage in its shifted position so long as the shift lever is depressed. then the shift lever is released the stop 110 will draw the lever 107 and the roller 106 forwardly to release the arm 105 and permit the platen to return to its lower position.

The case shift levers and their associated mechanism are arranged one at each side of the machine so that the platen may be shifted by either hand of the operator. The only :,eamee force necessary is that required to depress the shift lever against the tension of its spring and to move the contact mechanism. The force for lifting the platen is supplied by the solenoid. So long as the shift lever is held down the platen will remain in its upper position, but the force required for holding the key down is very small since the weight of the platen is not sustained by the key, but by the locking mechanism described. The force of impression made by the type bars may be controlled by shifting the fingerpiece 31 up or down. This moves the contact piece 32 so as to vary the period of con.- tact and thus regulate the force of the blow exerted by the type bar.

Another form of mechanism for regulating the period of contact is shown in Figs. 4 and 5. In this form the contact 32 is mounted on an insulating block 115 which is carried on an arm 116 having a rack 117 meshing with a worm 118. The worm 118. is provided with a knurled handle 119 which may be rotated to adjust the position of the contact 32 and thus regulate the force of theblow of the type bars in the manner already explained.

1. The combination with a typewriter having case shift mechanism, of a solenoid f or actuating said case shift mechanism, a shift key for controlling said solenoid, means for automatically cle-energizing said solenoid at the close of an operation thereof, a detent movable into position to retain said case shift mechanism in shifted position, a spring for moving said detent into operative relation with said case shift mechanism, and means connected with said shift key for holding said detent out of operative position when said shift key is released but permitting operation of said detent when said shift key is depressed.

2. The combination with a typewriter having case shift mechanism, of a solenoid for actuating said case shift mechanism, and a spring interposed between said solenoid and case shift mechanism arranged to permit excess movement of said solenoid when said case shift mechanism reaches the limit of its movement.

3. The combination with a typewriter having a shift frame, of a solenoid, for actuating said shift frame, a spring interposed between .said solenoid and shift frame to permit excess movement of said solenoid when said shift frame reaches the limit of itsl movement, and means for holding said spring under tension in the position to which it is moved by said solenoid.

4. The combination with a typewriter having a shift frame, of a solenoid, a spring interposed between said shift frame and solenoid to transmit movement from said solenoid to said shift frame and to permit excess movement of said solenoid when said shift frame has reached the limit of its movement, a shift key, and a detent controlled by said shift key for maintaining said spring under tension independently of said solenoid.

The combination with a typewriter having a shift frame, of a solenoid having a plunger for actuating said shift frame, a spring interposed between said plunger and shift frame for transmitting movement from said plunger to said shift frame, said spring being arranged to permit excess movement of said plunger after said shift frame reaches the limit of its movement, a shift key for controlling said solenoid, and a detent actuated by said shift key for maintaining the tension in said spring after said solenoid has been de-energized. y

(3. The combination with a typewriter having a shift frame, of a solenoid having a plunger for actuating said shift frame, a spring interposed between said shift frame and plunger to transmit movement from said plunger to said shift frame, a shift key for controlling said solenoid, means for automaticallyY del-energizing said solenoid at the close of an operation thereof, a detent for retaining said spring under tension after said solenoid has been dei-energized, and means for releasing said detent when said shift key is released.

7. The combination with a typewriter, of a solenoid for actuating said typewriter, a contact member for controlling said solenoid, a spring for closing said contact member, means for holding said Contact member open against the force of said spring, a key for releasing said holding mea-ns, and means for re-engaging said contact memberwith said holding means when said solenoid is energized.

8. The combination with a typewriter, of a solenoid for actuating said typewriter, a contact member having a fixed and a movable stop thereon, a spring for actuating said movable stop, a detent arranged to engage said fixed stop to hold said contact member open, means for shiftiner said detent out 0f engagement with said fixed stop to permit said contact member to close, and means for restoring said contact member to open position, said movable stop being operated by said spring to engage said detent when saidcontact member is restored to open p0- sitioif 9. The combination with a typewriter, of a solenoid for actuating said typewriter, an electric circuit for energizing said solenoid,

' a contact member for controlling said electric circuit, said contact member having a fixed and a movable stop thereon, a spring for operating said movable stop, a detent for engaging said fixed stop to hold said contact member open, key controlled means for shifting! said detent to release said fixed shift from said movable stop to said fixed slop. said delent operating' to move said stop npon return movement of said key conl0 movable slop against the tension of said trolled means. spring. and mean.` for restoring said contact In testimony whereof we have signed our 5 member to open position. said movable stop names to this specification on this second i being freed to engage said detent and retain da)v of October A. D. 19:25.

said Contact member in open position when OTTO A. H(')KANSON. x so restored, said detent being arranged to JAMES F. HOCA. is 

